test if an accelerator can be stored

gtk_accel_map_change_entry can't change accelerators
to keys like arrows. Test this and show the keys in the list
only if they can be really changed.

https://sourceforge.net/tracker/?func=detail&aid=2805139&group_id=222125&atid=1054680

diff --git a/src/preferences.c b/src/preferences.c
index ba5e97f..0703034 100644 (file)
--- a/src/preferences.c
+++ b/src/preferences.c
@@ -994,11 +994,24 @@ static void accel_store_edited_cb(GtkCellRendererAccel *accel, gchar *path_strin
        GtkTreeModel *model = (GtkTreeModel *)accel_store;
        GtkTreeIter iter;
        gchar *acc;
+       gchar *accel_path;
+       GtkAccelKey old_key, key;
        GtkTreePath *path = gtk_tree_path_new_from_string(path_string);
 
        gtk_tree_model_get_iter(model, &iter, path);
-       acc = gtk_accelerator_name(accel_key, accel_mods);
+       gtk_tree_model_get(model, &iter, AE_ACCEL, &accel_path, -1);
 
+       /* test if the accelerator can be stored without conflicts*/
+       gtk_accel_map_lookup_entry(accel_path, &old_key);
+
+       /* change the key and read it back (change may fail on keys hardcoded in gtk)*/
+       gtk_accel_map_change_entry(accel_path, accel_key, accel_mods, TRUE); 
+       gtk_accel_map_lookup_entry(accel_path, &key);
+
+       /* restore the original for now, the key will be really changed when the changes are confirmed */
+       gtk_accel_map_change_entry(accel_path, old_key.accel_key, old_key.accel_mods, TRUE); 
+
+       acc = gtk_accelerator_name(key.accel_key, key.accel_mods);
        gtk_tree_model_foreach(GTK_TREE_MODEL(accel_store), accel_remove_key_cb, acc);
 
        gtk_tree_store_set(accel_store, &iter, AE_KEY, acc, -1);